I am talking about ALL printers. I own 14 printers and one of them is a Prusa i3 MK2S. I also have a Lulzbot, several SeeMeCNC Rostock MAX (V1, V3), Ultibots D300VS and D300VS+, Mini Kossel, K250 delta, a home brew CoreXY, a Huxley (RepRap), and several others.

Before calibrating flow rate, Preload and destring, your extruder needs to be well calibrated. Calibrating an extruder is a bit of a chore so I developed a 3D printable fixture to hold a common digital caliper. I show how to use this to easily calibrate your extruder's E-steps. Here's the video: [url=Here's a tutorial on calibrating your extruder. I needed to complete this before publishing the KISSlicer Calibration Wizards to calibrate flow rate, Preload, and destring. All of these require a well calibrated extruder.

My technique uses a simple (and inexpensive) digital caliper and a 3D printed tool that I developed to simplify and improve the calibration process. The printable files are linked in the video's description. Here is the video: Extruder E-step Calibration

Awesome videos Michael. It's not easy to give a presentation without a lot of "ums" and on the fly searching for the right word, but you did. Your videos contain a lot of helpful information and are very smooth.